| 摘要 |
Process for the production of precipitated silica from olivine including the following steps:- providing olivine particles with a particle size preferably below 1 mm in diameter,- preferably mixing olivine and water to form an olivine/water slurry,- mixing the olivine/water slurry with hydrochloric acid (HCI), preferably at a concentration at 18 wt% or above, and at a temperature preferably between 50 - 130°C, and reacting for a period of time, preferably between 20 - 360 minutes,- removal of coarse mineral impurities (sand product),- separation of precipitated silica from mother solution,- mechanical treatment of the separated precipitated silica and optionally some water to obtain a slurry,- preparation of a low viscosity slurry by adding sodium aluminate or another suitable aluminate, preferably to 100 - 6000 p.p.m., and adjusting the pH, preferably to values between 4 – 9,- ageing at a temperature between 50 - 150°C according to product requirements,- dispersion of silica slurry,- removal of fine mineral impurities (sand product),- drying of the silica. |
